Efforts are continuing along four projects: The synthesis of 1) erythronolide, 2) the chiral synthesis of Prostaglandins from glucose, 3) the synthesis of histrionicotoxin and 4) a general route to tetracycline. On 1), we are concentrating on finding stereospecific routes for the stereospecific formation of a tertiary methyl carbinol from an alpha-alkoxy ketone and on joining the fragments which have been synthesized. On 2), we are seeking more flexible routes in the general scheme which involves Claisen rearrangement to establish carbon chirality from sugars. On 3), a major problem is the regiospecific opening of an aziridine ring, or devising alternative methods for the stereospecific formation of cyclohexylamines. On 4), we are planning to complete the synthesis of anhydrodesoxy tetracycline and to extend it to anhydrotetracycline and hence to tetracycline itself.